Electric switch



Oct. 12 1926.

W. E. MENZIES ELECTRIC SWITCH Filed Feb. 19,

IINVENTOR W/'// /'am f. Menzies,

WITNESSES: @.&.%

ATTORN EY Patented Oct. 12, 1926.

UNITED STATES PATENT OFFICE.

WILLIAI EQIINZ IIS, OI WILKIHSBUBG, PENNSYLVANIA, ASSIGNOR T WESTING-HOUSE ELECTRIC & nlwrac'rume COKPANY, -A CORPORATION OF PENNSYL- VAHIA.

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Application filed l 'ebruary 18, 1921. Serial No. 446,309.

My invention relates to electric switches and articularly to those ofthe quick-make and reak type.

One of the objects of my invention is to provide a switch of thecharacter described wherein quicknessand accuracy of movement aresecured by the use of a minimum number of parts. i 1

Another of: the objects of my invention is to provide a switch-actuatingmechanism of such construction as to insure against suspension ofmovement of the tensioned members when the line dividing the op ositeangles of pressure is reached, in or er to lessen the tendenc of thecontact members to spark and to t ereby conserve their life andeificiency.

Still another object of my invention is the provision of means wherebythe tension of an actuating spring is directed against a striker arm forthe movable contact member and wherein such striker arm is pivotallysupported on the movable contact member in such position that thepressure of the spring is directed against such well as against thepoint 0 striking engagement between the striker arm and the movablecontact member, thereby increasing the effectiveness of the spring.

I accomplish the foregomg ob]ect s by means of two memberspivotedeccentrically to each other, one of them havin lost-motionengagement with a movab e contact member and each supporting one of theends of a tension spring in such manner that, when the actuating memberis moved a distance sufiicient to carry the spring across the centerline of one of the pivots, the direction of tension on the other member,or striker arm, will be shifted. The striker arm, by reason of itslost-motion connection to the movable contact member, will strikethe-movable contact member a hammer blow during its movement. to thereverse position, under the action of the sprin and will carry themovable contact mem r to open or to closed position, as the case may be.

As shown in the accompanying drawings:.

ivotal point, as

Figs. 4, 5 and 6 are detail views of the movable contact carrier, thestriker arm and the operating lever, respectively.

The switch is mounted on a base 7 and consists of a stationary contactmember 8, a movable contact member 9, a striker arm 10, an operatinglever 11 and a pair of springs 12.

The operating lever 11 and the movable contact'member 9 areindependently pivoted at 13 to the base 7, and the striker arm 10 ispivoted at 14 to the movable contact member 9. The striker arm 10 isprovided with a slot that co-operates with a lugv 15 on the striker armto constitute a lostmoti'on connection between the movable con tactmember and the striker arm.

The movable contact member 9 is provided with a usual tip 16 thatismoved into and out of engagement with a tip 17, and these contact tipsare connected respectively to terminals 18 and 19.

When the operating lever 11 is in its lower or open position, as shownin Fig. 1, the tension of the springs 12 serves to maintain the movablecontact member 9 in open position, by reason of the engagement betweenthe striker arm 10 and the lug 15. It will be seen that the striker arm10 abuts against the lever .11 to limit the movement ofboth of suchmembers toward their open positions. It will be noted that the rotationof said members about the pivot 13 is limited by reason of theengagement between the outer end of the movable contact member 9 and theunder side of the terminal 18, and also by reason of the en agement ofthe lever 11 with an end wal 20 of the. base 7.

Upon movement of the operating lever 11 toits upper or closed position,the springs 12 are carried across the pivots 13 and 14, causing thestriker arm 10 to be thrown to the position illustrated in Fig. 2, andto thereby move the contact member 9 to closed position. When in thisposition, the tension of the springs 12 is directed against the hit till

posite the ends of the pivot 13. Pressure is thus imparted against themovable contact member, through the pivot 14, in addition to, andirrespective of, the pressure exerted thereon through the striker arm 10and the lug 15. When the line of tension as exemplified by the springs12, has crossed the pivot let, the striker arm 10 will be im mcdiatelythrown to the position illustrated in Fig. 1, thereby eli'ecting a quickopening of the switch and minimizing the tendency to arc.

' During closing movement ofthe lever 11, the spring is carried acrossthe pivot 13, in advance of its passage across the pivot 14, and thereis, consequently, not the same degree of pressure exerted on the movablecon tact member by the spring at the early stages of its closingmovement that is present at the start of its opening movement, but thenecessity for such efiectiveness is not as great during the closing movement, because there is less tendency of the contacting tips to are whenthey are moving toward one another.

While l have shown two springs 12, one spring would suflice, the twosprings being provided merely to secure a balancin of the tensionexerted on the pivots an to overcome any tendency to bind.

A. tension spring 22 is provided for returning the operating lever 11 toits open position when the switch is to be used as a control switch andit is desired to guard against permitting it to be inadvertently left inclosed position. This spring has one end fastened to the operatin leverand its other end secured at any lined point 23 adjacent to the switch.

It will be a parent that the invention may be applie to a variety ofswitches. For instance, it may be conveniently employed in connectionwith multi-pole switches wherein the movable contact memher will, ateach actuation thereof, close a circuit through any one of a pluralityof stationary contact devices, as desired.

Various other modifications will be readily apparent to those familiarwith the art, and t e scope of my invention is limited only as deiinedin the claims appended hereto.

ll claim as my invention 1. An electric switch comprising, incombination, a movable contact member, a striker arm pivoted thereon andhavin a portion thereof adapted to make lOSt-IIlOtlOIl engagement withthe movable contact member, a pivoted operating lever, and resilientmeans between the operating lever and the striker arm so positioned asto move across the pivotal point of the striker arm in advance of itspassage across the pivotal support for the operating lever when theswitch is being moved to open position.

2. An electric switch comprising, in combination, a movable contactmember, a striker arm pivoted thereon and having a portion thereofadapted to make lost-motion engagement with the movable contact member,a pivoted operatinglever, and a tension device between the operatinglever and the striker arm so positioned as to move across the pivotalpoint of the striker arm in advance of its passage across the pivotalsupport with the operating lever, when the switch is being moved to openposition, and to cross the point of pivotal support for the operatinglever in advance of thepivot for the striker arm when the switch isbeing moved to closed position.

3. A. switch comprising, in combination, a movable contact member and anoperating lever both mounted on a fixed pivot, a striker arm pivoted onthe movable contact member at a point removed from the said fixed pivot,a lost-motion connection between the outer end of the striker arm andthe movable contact member, and means for biasing the operatin lever andthe striker arm toward each other, the parts being so positioned thatthe line of force will pass across the movable pivot in advance of itspassage across the fixed pivot when the switch is being moved toward oneof its positions.

i. A switch comprising, in combination, a movable contact member and anoperating lever both mounted. on a fixed pivot, a striker arm pivoted onthe movable contact member at a point removed from the said fixed pivot,a lost-motion connection be tween the outer end of the striker arm andthe movable contact member, and a spring connecting the operating leverand the striker arm, the parts being so positioned that the line outtensional force will pass across the movable pivot in advance of itspassage across the fined pivot when the switch is being moved toward oneof its positions and will move across the fixed point of pivotal supportin advance of the movable pivot when the switch is being moved to itsother position.

5. An electric switch comprisin,.,in combinatign, a pivotally supportscontact member, an operating lever for said mem her, a striker arm,means for exertin tension between the operating lever an the movablecontact member, and means whereby, during an opening movement of theswitch, the striker arm is caused to impart an opening movement to themovable contact member in advance of the passage of the line oftensional force across the pivotal point of the movable contact member.

In testimony whereof, I have hereunto subscribed my name this 8th day ofFebruary, 1921.

